Esters of perfluoro-tertiaryalkyl alcohols and hydrocarbyl or holo-hydrocarbyl carboxylic acids

ABSTRACT

An ester condensation product of (1) a perfluoro-tertiary-alkyl alcohol in which the perfluoro-alkyl group has not more than 20 carbon atoms, is directly bonded to the alcoholic hydroxyl radical, and has at least one perfluoro-methyl group bonded to the tertiary carbon atom, and (2) an organic acid of not more than 18 carbon atoms with at most double bond unsaturation and selected from the group consisting of a hydrocarbon carboxylic acid, a hydrocarbon sulphonic acid, a hydrocarbon phosphonic acid, a hydrocarbon silicic acid or cyanuric acid, or a halogen substituted counterpart thereof. Illustrative uses of these esters include inert heat exchange fluids, as polymerizable monomers, textile treatment, surface active agents, and the like.

United States Patent Pavlik [451 June 6, 1972 [54] ESTERS 0F PERFLUORQ-[56] References Cited TERTIARYALKYL ALCOHOLS AND UNITED s ATEHYDROCARBYL 0R HOLO- T S PATENTS HYDROCARBYL CARBOXYLIC ACIDS 2,642,4166/1953 Ahlbrecht et a1. ..260/83.5 2,826,564 3/1968 Bovey et a1...260/83.5 [72] Inventor: Frank J. Pavlik, West St. Paul, Minn.2,921,957 0 O'Rear ct alum 260/485 [73] Assignee: Minnesota Mining andManufacturing 3,030,409 4/1962 Andreades et 260/488 Company, St PaulMinn 3,047,610 7/1962 Brace at 8.1 ..260/463 2,472,812 6/1949 Dickey..260/486 H Filed: p 17, 1970 2,754,316 7/1956 Conly ..260/633 x [271]AppL 28,242 2,863,906 12/1958 B aranauckas et a1. .260/486 H X 3,022,2922/1962 Sims ..260/486 H X Related U.S. Application Data PrimaryExaminer-Floyd D. Higel [63] Continuation f 1966 Attorney-Kenney,Alexander, Sell,Steldt& Delahunt abandoned, which 18 acontinuation-in-part of Ser. No. 246,022, Dec. 20, 1962, abandoned,which is a continuation of Ser. No. 234,222, Oct. 30, 1962, Pat. No.[57] ABSTRACT 3,385,904. An ester condensation product of (l) aperfiuoro-tertiaryalkyl alcohol in which the perfluoro-alkyl group hasnot more [52] U.S. Cl. ..260/47l C, 8/1 15.6, 1 17/1395 CQ, than 20carbon atoms, is directly bonded to the alcoholic 117/142, 117/154,252/86, 252/81, 252/875, hydroxyl radical, and has at least oneperfluoro-methyl group 2 2 bonded to the tertiary carbon atom, and (2)an organic acid of 2 /77- BB, 260/861 E, 260/3468, 260/348 R, not morethan 18 carbon atoms with at most double bond un- 260/4 R, 2 2, 2260/456 saturation and selected from the group consisting of a 2 /4 P, 2260/485 260/486 hydrocarbon carboxylic acid, a hydrocarbon sulphonicacid, a 2 /4 7, 2 F, 2 94, 2 14 F. 2 hydrocarbon phosphonic acid, ahydrocarbon silicic acid or R, 260l635 cyanuric acid, or a halogensubstituted counterpart thereof. 11' 69/14, C079 69/54: C079 101/68lustrative uses of these esters include inert heat exchange [58] Fieldof Search ..260/486 N, 487, 488, 448.8, fluids, as polymerizablemonomersy il treatment surface 260/248, 456, 961, 471 C, 469, 475 F, 486H, 488 active agents and 1 F, 488 H, 488 J 6 Claims, No Drawings ESTERSOF PERFLUORO-TERTIARYALKYL AIJCOHOLS AND HYDROCARBYL OR HOLO-HYDROCARBYLCARBOXYLIC ACIDS This application is a continuation of Ser. No. 538,556,filed Mar. 30, 1966 (now abandoned), which is a continuation-inpart ofSer. No. 246,022, filed Dec. 20, 1962 (now abandoned), which is acontinuation of Ser. No 234,222, filed Oct. 30, 1962, now US. Pat. No.3,385,904.

This invention relates to a process for the treatment of fluorinatedcyclic ethers having at least four carbon atoms to produce fluorinatedtertiary alcohols and the production of derivatives of the alcohols soproduced. In one aspect this invention relates to new and usefuloxygenated derivatives produced from such fluorinated cyclic ethers andthe corresponding tertiary alcohols.

Perfluorinated cyclic monoethers are known in the art. Theperfluorinated cyclic monoethers are prepared as products and byproductsfrom the electrochemical cell as disclosed in [15. Pat. No.2,5l9,983-Simons, issued Aug. 22, 1950. Specific perfluorinated cyclicmonoethers and the method of preparation thereof by the electrochemicalcell are disclosed in U.S. Pat. No. 2,594,272 Kauck et 21., issued Apr.29, 1952, and in US. Pat No. 2,644,823 Kauck et al., isued July 7, 1953.

The perfluorinated cyclic monoethers having at least four carbon atomsare useful as refrigerants, solvents, dielectric or insulating fluids,etc. They are noted for their chemical and physical stability and fortheir solvent action. These compounds are difficult to use as reactantsor to convert to other chemical compounds, and few, if any, reactionswith these compounds are known in the art. Since the perfluorocyclicmonoethers having at least four carbon atoms are available in the art asa direct product and as a byproduct, it is much to be desired to providea method for the conversion of these cyclic monoethers to other chemicalcompounds which are useful.

It is an object of this invention to provide a process for theconversion of pertluorocyclic monoethers to other compounds.

It is another object of this invention to provide a new method formaking perfluorinated tertiary alcohols.

Another object is to provide a method for the conversion of fluorinatedtertiary alcohols to other useful compounds.

It is another object of this invention to provide new and usefulcondensation products of fluorinated tertiary alcohols, such as theesters and ethers.

Various other objects and advantages of the present invention willbecome apparent to those skilled in the art from the accompanyingdescription and disclosure.

According to this invention, a perfluorocyclic monoether in which one ofthe vicinal carbon atoms is completely substituted with perfluoroalkylradicals is decyclized in contact with hydrogen fluoride with or withoutthe presence of a decycliution catalyst under conditions such that thecyclic ether chain is opened to produce the corresponding tertiaryalcohol. The perfluorocyclic monoethers can be decyclized in thepresence of catalysts, such as antimony pentafluoride, cesium fluoride,activated carbon and pyridine. 'fl'ne temperature conditions utilizedare from about 20 C. to about 350 C. and pressures utilized areatmospheric or substantially elevated.

The perfluorocyclic monoethers as the starting compounds of thisinvention are designated perfluoroisoalkylene oxides 1,2 and thepreferred ethers are represented by the following typical formula:

t R:C --CF2 in which R,is defined as a perfluoroalkyl radical oflessthan carbon atoms, preferably of one to four carbon atoms, and

preferably at least one K is a perfluoromethyl radical.

Exampla of perfluorocyclic monoethers falling within thefluoroisobutene-oxide- 1,2; perfluoro-Z-methylbutne oxide- 1 2; andperfluoro-Z-methylpentene oxide-1,2.

The amount of hydrogen fluoride is not critical except insofar as atleast stoichiometric amounts in relation to the cyclic ether arerequired, but large excesses may be used without departing from thescope of this invention. 'lhe quantity of decycliaation catalyst, ifused, may vary over a considerable range. Usually the weight ratio ofperfluorocyclic monoether to decyclization catalyst is between about 1:5and 10:1.

The typical equation for the reaction involved for the perfluorocyclicmonoethers is shown below:

In accordance with one embodiment of this invention, theperfluoro-tertiary alcohols are converted to new and useful organiccondensation products containing a perfluoro-tertiaryalkyl group inwhich the alkyl group contains at least one, preferably at least two,perfluoromethyl groups, and the perfluoro-tertiary-alkyl group has notmore than 20, preferably 10, carbon atoms.

The new condensation products of this invention are obtained by reactingthe above perfluoro-tertiary alcohol with an anionogenic organiccompound of not more than 20 carbon atoms (an organic compound which isnormally unionized but which is capable of generating a negative ion,anion, during the condensation reaction) by heating a mixture of thesame, preferably in the presence of an organic solvent or liquid refluxmedium. Particular examples of condensation products of theperfluoro-tertiary alcohol are the esters of organic acids (includinganhydrides or acid halides) and ethers of aliphatic halides.

In the case of the esters, the organic acid moiety may be acyclic,alicyclic, aromatic or heterocyclic and may be saturated or may containdouble bond unsaturation, such as ethylenic unsaturation. Preferably theorganic acids contain at most halogen substitution, such as fluorine,chlorine or bromine. Examples of the acid moiety of the ester includecarboxylic, sulfonic, phosphonic, silicic, or cyanuric organic acidshaving not more than 18 carbon atoms. The esters of hydrocarboncarboxylic and hydrocarbon sulfonic acids are preferred.

In the case of the ethers, the aliphatic halide contairs nonvinylichalogen such as fluorine, chlorine, bromine or iodine and may be acyclicor alicyclic, either saturated or ethylenically unsaturated. Preferablythe aliphatic halide hm at most halogen, hydroxyl or carboxysubstitution. Examples of aliphatic halides include alkyl halide,alkylene halide, hydroxy alkyl halide and alkyl haloester having notmore than 16 carbon atoms.

The perfluoro-tertiary alkyl condensation derivatives of this inventionare particularly useful a surfactants and for apply ing to surfaces,preferably in polymerized form, to render such surfaces, such asfabrics, oil and water repellent.

As previously mentioned, the perfluorocyclic monoether startingcompounds can be prepared from the electrochemical cell. These etherscan also be prepared by oxidation of perfluoroolefins with hydrogenperoxide in an aqueous alkaline solution, such as in the presence of anaqueous alkali carbonate solution, eg sodium carbonate, at a temperaturebetween about0C. andabout 50 C.

The following examples are ofi'ered m a better understanding of thepresent invention and relate to the conversion of the perfluorocyclicmonoethers and their useful derivatives such as the perfluoro-tertiaryalkyl esters and ethers (oxy alkylene esters),andtheexamplesarenottobeconstruedasunnecw scope of the startingcompounds of this invention include persarily the invention.

EXAMPLE I To 10 ml. of acetone and 31 gs. of 30 percent hydrogenperoxide at C., in a two-neck, one-liter glass flask with a magneticstirrer and dry ice condenser was added 27 gs. (0.135 rn.) ofperfluoroisobutene. Water, 75 ml., containing gs. Na CO and 16 gs. Na i-PO was added dropwise during two hours. Stirring was continued for anadditional twenty minutes. The product was distilled out through the dryice condenser into a vacuum system. There was obtained 13.3 gs. ofproduct, a 46 percent yield. Infrared spectroscopy indicated about 95percent perfluoroisobutene oxide and no olefin.

EXAMPLE II To 5 gs. of perfluoroisobutene oxide-1,2 in an Aminco 200-ml. bomb was charged 10 ml. of anhydrous liquid hydrogen fluoride. Thebomb was placed in the Aminco rocker and heated and rocked at 250 C. for64 hours. It was then cooled and the contents distilled through a tubecontaining sodium fluoride pellets to take up the unreacted hydrogenfluoride. The recovered fluorocarbon was condensed out in two fractions.The first fraction contained no unreacted perfluoroisobutene oxide andonly a small amount of perfluorotertiary-butyl alcohol. The second orresidue fraction contained a larger amount of perfluoro-tertiary-butylalcohol as indicated by a definite infrared absorption at 2.7 microns.

EXAMPLE III To gs. of anhydrous hydrogen fluoride and 5 gs. of antimonypentafluoride in a 300 ml. stainless steel autoclave was charged 35 gs.of perfluoroisobutene oxide from Example I. The mixture was agitated inan Aminco rocking mechanism at 100 C. for 16 hours. The product was thendistilled out in vacuum through a steel tube containing sodium fluoridepellets to react with the excess hydrogen fluoride. There was obtained21 gs. of perfluoro-tertiary-butyl alcohol by distillation of thecondensed fluorocarbon. It boiled at 48 C. and showed a hydroxyabsorption in the infrared region at 2.7;L. Nuclear magnetic resonanceindicates the alcohol structure. The pKa of this material was determinedto be about 5.5.

EXAMPLE IV Sodium perfluoro-tertiary-butylate, 4.76 gs., was preparedfrom sodium metal and perfluoro-tertiary-butyl alcohol of Example III inanhydrous ethyl ether at 5 C. initially, then gradually warming to 25 C.The ether, after filtration of the solution from insoluble salts, wasremoved in vacuum at 1 mm. and 40 C. To this salt was added 50 ml.petroleum ether (dried over P 0 a trace of pyrogallic acid and 1.7 gs.acrylyl chloride. The reaction was stirred at room temperature for 64hours. The mixture was filtered, washed with aqueous sodium bicarbonateand water and finally dried over Drierite and sodium sulfate.Distillation through a l0-plate column gave 2.3 gs. of product boilingat 99 101 C. A yield of 43 percent was obtained. Gas liquidchromatography indicated a purity of 98 percent. Infrared spectroscopyindicated perfluoro-tertiarybutyl acrylate by absorptions at 5.5g, 6.1g.and 7.8;. This material when polymerized and applied on textiles gaveoil and water repellency to the textile.

EXAMPLE V Perfluorotertiarybutyl methacrylate was prepareizl fromperfluoro-tertiary-butyl alcohol and methacrylyl chloride with 2-methylpyridine as the acid acceptor without added solvent. The yield was 78percent. The boiling point was C./0.5 mm. This material is useful as amonomer for making plastics and resins.

EXAMPLE VI Sodium perfluoro-tertiary-butylate, 15.3 gs. (0.059 rn.),prepared in a manner similar to Example IV, and 0.08 m.

ethylene bromohydrin were heated at reflux in methylethyl ketone for 88hours. An percent yield of Z-(perfluoro-tertiary-butoxy) ethanol (CFCOCH CI-I OI-I boiling at C./740 mm. was obtained by distillation.Ethylene oxide and the perfluoro tertiary-butyl alcohol or the sodiumsalt thereof gave the same product as above, but also higher boilingliquids. This material is useful for conversion to acids and esters anddirectly as a solvent and a plasticizer.

Preparation of the methacrylate of the above2-(perfluorotertiary-butoxy) ethanol was accomplished as follows: To 9gs. (0.032 m.) of tert-C F OCI-I CH OH were added 5 gs. (0.048 m.) ofCH: C(CHQCOCI, 20 ml. of ethyl ether and 0.05 m. of pyridine and themixture was stirred overnight at room temperature. Distillation gave 7.2gs. of perfluoro-tertiary-butoxy ethyl methacrylate, boiling at 35 C./1mm. Analysis by infrared spectroscopy indicated an unsaturated ester.Polymerization of this monomer afforded a polymer which showed water andoil repellency for application to textiles and leather as a protectivecoating.

The following derivatives are also made by reaction of the aboveZ-(perfluoro-tertiary-butoxy) ethanol with diisocyanates, diacids,silanes and the like;

perfluoro-tertiary-butoxy ethyl (isocyanotoluene) carbamate GH-C-OCHzCHzO C (0 r3).

0 CH-'I-O-CHzCHzOC (C F di-perfluoro-tertiarybutoxy ethyl maleate C-OCHzCHzO C (C F3):

0 iO CHzCHzO C (0 F di-perfluoro-tertiary-butoxy ethyl phthalate [(0 F90 0 CHzCHzOlzSiClz dichloro, di(perfiuoro-tertiary-butoxyethyloxy)silane EXAMPLE VII Calculated Found C 25.7 27.0 S 6.8 7.3 F36.4 34.2

Perfluoroalkyl arylsulfonates are useful for making many organicchemicals containing the perfluoroalkyl group, such as ethers, halides,alkylbenzenes, etc.

Perfluoro-tertiary-butyl chlorosulfonate has also been synthesized inthe above manner using sulfuryl dichloride and has similar utility.

um n "14' EXAMPLE VIII From 12.45 gs. (0.075 m.) of ethyl bromoacetateand 19.35 gs. (0.075 m.) of NaOC(CI-";,) in ml. of methyl-ethyl ketonestirred and heated at reflux 73 hours there was obtained 13 gs. (50percent of ethyl(perfluoro-tertiary-butoxy) acetate boiling at 140-145C./750 mm. Hydrolysis of this ester in 12 percent aqueous sodiumhydroxide overnight at room temperature gave after acidification andextraction (perfluoro-tertiary-butoxy) acetic acid which crystallizedfrom ether-hexane and melted at 85-87 C.

A chrome complex was made from this acid, and paper and leather weretreated with its solution in isopropyl alcohol. The results indicatedgood water and oil repellency properties of the treated paper andleather. Other derivatives of this acid can bemade which are useful inpaints, plastics. elastomers, i.e., vinyl esters as monomers and diolesters as plasticizers.

EXAMPLE 1X1 To 10 ml. of methyl ethyl ketone were added 5.16 gs. (0.02m.) NaOC(CF and 4.66 gs. (0.02 m.) 1 l-bromoundecene. To promote thereaction, 0.35 g. Nal was added and the reaction heated for 192 hours atreflux. Filtration yielded a total of 1.15 g. of a mixture of NaBr andNal or 56 percent conversion based on NaBr content. Distillation of thefiltrate through a three-plate column gave 3.18 gs. ofll-(perfluoro-tertiary-butoxy) undecene boiling at 56 C./0.5 mm., d.1.22,

Infrared spectroscopy indicated the characteristic absorptions forunsaturation and fluoro-carbon.

Derivatives of this material can be made as follows:

HOH

' O Hz-JJO Other similar w-bromoundecyl derivatives can be made, such asalcohols and acids. These derivatives are useful as plasticizers andmonomers for making polymers.

EXAMPLE X To 0.87 g. (0.005m.) of 2,4toluene-diisocyanate in 5.2 gs. ofethyl acetate was added a trace of phenyl mercuric acetate and 2.36 gs.(0.01 m.) perfluoro-tertiary-butyl alcohol. The ampoule was sealed andheated at 100 C. and agitated for 17 hours. An infrared spectrum of therecovered solution showed the diurethane,di-perfluoro-tertiary-butyl-toluene dicarbamate, was present in theproduct and useful for' making urethane type resins.

EXAMPLE X1 1 To 13.0 gs. 0.05 m.) NaOC(CF -was added ml. dry petroleumether (boiling at -60 C.). This was cooled to 80 C., and 16.4 gs. of CH,SiCl (0.1 m.) was added and stirred overnight at -80 C. The reactionmixture was warmed to 50 C. and stirred 20 hours. After cooling, themixture was filtered and the filtrate distilled through a three-platecolumn. There was obtained 6.0 gs. of a fraction, boiling at 9799 C.,containing some EtSiCl and 3.5, gs. of dichloro-ethyl-perfluoro-tertiary-butoxy silane which boiled at 99 C. Infrared analysis ofthe latter indicates the above material. This product can be hydrolyzedwith water to produce a silicone useful for coating textile fabrics.

EXAMPLE XII NaOC (CF9 6.45 gs., (0.025 m.) in acetone, was added to 5gs. (0.055 m.) cyanuric chloride in acetone at 0 C. during 105 minutes.Overnight stirring, 22 hours, was conducted at room temperature. Thereaction mixture was then filtered and the acetone removed from thefiltrate in vacuum. There was recovered 2.5 gs. of light yellow liquidand unreacted cyanuric chloride. Infrared indicated desiredperfluoro-tertiary-butyl dichlorocyanurate. This is useful for reactionwith amines and subsequently with formaldehyde to produce textiletreating resins.

[EXAMPLEXIII From 3.87 gs. (0.03 m.) (Cl-l SiCl and 15.4 gs. (0.06 m.)NaOC(CF;,) in 35 ml. petroleum ether 30-60 C., there was obtained after68 hours at reflux 6.0 gs. of distilled lO-plate column) product,boiling at 146 C. Infra-red analysis indicated no OH or carbonylabsorptions. Thus the product was (Cl-I Si(OC ,F useful as a solvent.

EXAMPLE XIV To 2.2 gs. triethyl amine and 4.72 gs.perfluoro-tertiarybutyl alcohol in 10 ml. dichloromethane at 0-5 C. wasadded drop-wise and with stirring 5.64 gs. perfluoro-methane sulfonicanhydride. Stirring at room temperature was continued 88 hours. Thevolatile material was then dis-tilled from the nonvolatile in vacuum,then redistilled. There was obtained 3.6 gs. at a boiling point of 91 C.Analysis by infrared and NMR spectroscopy indicated the desiredmaterial, perfluorotertiary-butyl perfluoromethanesulfonate, which isuseful as a plasticizer for fluorocarbon resins.

EXAMPLE XV 8.6 gs. (0.033 m.) NaOC(CF 4.0 gs. ClCl-l CHOHCH OH and 4.0gs. ethylene glycol and 9 ml. methylethyl ketone were heated at reflux67 hours. 1.64 gs. of salts were filtered off; theory 1.93 gs. Theproduct was phased out by adding water and washed three times withwater. There was recovered 9.0 gs. of product which was dried overDrierite. Distillation through a four-plate column at 1 mm. gave 4.06gs. of a fraction boiling at 60-65 C.,

Infrared indicated C.,E OCI-I CHOI-ICI-I OH, useful for preparation ofpolyurethanes and polyesters.

EXAMPLE XVI To 2.1 gs. 0.02 m.) of 2-methylpyridine, cooled to 0-5 C.,was added dropwise with stirring 4.2 g. of trifluoracetic anhydride.Then 4.72 g. of perfluoro-tertiary-butyl alcohol was added to the abovemixture. Stirring was continued at room temperature for 48 hours.Distillation of the reaction mixture gave P perfluoro-tertiary-butylperfluoroacetate boiling at 57-58 C. at 740 mm. Infrared spectroscopy ofthe sample showed ester absorption at 5.4;L. This compound is useful asa low boiling inert heat exchange liquid.

EXAMPLE XVII This perfluoro-tertjary-butoxy acid was prepared bydissolving 2.6 gs. (0.01 m.) of (CF -,CONa and 4.1 gs. (0.014 m.)"BKCHQMCOAEHF, in 15 ml. of methyl ethyl ketone and heating the solutionat reflux. about (1, for hours.

The solvent was stripped under vacuum and replaced by 50 ml. ofconcentrated isopropyl alcohol containing 2 gs. of dissolved KOH, Thesolution was refluxed for 2 hours. The isopropyl alcohol was thenevaporated under vacuum and 10 ml. of concentrated aqueous l-ICl addedto neutralize the base and liberate the acid. The aqueous solution wasthen extracted with 50 ml. of isopropyl ether, in several portions, andthe ether extract evaporated. An aqueous solution of the sodium salt ofthe acid was prepared by dissolving 0.3 gram of the residue in 30 ml. ofwater and neutralizing with dilute aqueous sodium hydroxide to thephenolphthalein end point. The resulting 1 percent solution showed asurface tension at 24 C. of 20 dynes per sq. cm. This surface tension isabout the same as is shown by a 1 percent solution of sodium perfluorobutyrate, which contains approximately twice the fluorine content as thepresent acid. This compound is very good as a surfactant or to treattextiles or leather for oil and water repellency when converted to thechrome complex.

EXAMPLE XVIII (CF CO(CH CH O),,H was prepared in a sealed glass ampoulefrom the reaction of 3.5 grams (0.076 mole) of ethylene oxide with 1gram (0.0035 mole) (CF COCH CH OH and 50 mg. KOH at 100 C. andautogeneous pressure for 16 hours. From the ratio of reactants, theaverage value of n in the polyether alcohol would be about 20. A 1percent aqueous solution showed a surface tension of 28 dynes per sq.cm. at 25 C. The starting alcohol, (CF COCH CH OH, in a l percentaqueous solution showed a surface tension of 41 dynes. This compound isuseful as a surfactant or can be converted to the acrylate andpolymerized and then used to treat fabrics for oil and water repellency.

Various alterations and modifications of reaction conditions may becomeapparent to those skilled in the art without departing from the scope ofthis invention.

What is claimed is:

1. Ester of l) perfluoro-tertiary-alkyl alcohol in which theperfluoro-alkyl group has not more than 20 carbon atoms, is directlybonded to the alcoholic hydroxyl radical, and has at least oneperfluoro-methyl group bonded to the tertiary carbon atom, and (2) anorganic acid of not more than 18 carbon atoms with at most double bondunsaturation and selected from the group consisting of hydrocarbyl orhalohydrocarbyl carboxylic acid.

2. An ester of claim 1 in which the perfluoro-tertiary alkyl alcohol isperfluoro-tertiary butyl alcohol.

3. Perfluoro-tertiary-butyl acrylate.

4. Perfluoro-tertiary-butyl methacrylate.

5. Di-perfluoro-tertiary-butyl toluene dicarbamate.

6. Perfluoro-tertiary-butyl perfluoroacetate.

2. An ester of claim 1 in which the perfluoro-tertiary alkyl alcohol is perfluoro-tertiary butyl alcohol.
 3. Perfluoro-tertiary-butyl acrylate.
 4. Perfluoro-tertiary-butyl methacrylate.
 5. Di-perfluoro-tertiary-butyl toluene dicarbamate.
 6. Perfluoro-tertiary-butyl perfluoroacetate. 